- Water System Facilities Plan
A water facilities study was conducted for the City of Harrisonville to determine and prioritize improvements designed to reduce taste, odor and manganese in the potable water while expanding the water supply, treatment and distribution facilities to meet a maximum daily capacity of 3 million gallons per day (MGD). The city's water treatment plant treats water from Lake Harrisonville and had a rated capacity of 2.4 MGD. The raw water quality is highly variable and difficult to treat.
Lake Harrisonville was evaluated to determine the firm yield of the lake in its current condition and after sediment removal. The lake has a firm yield of 1.4 MGD and is capable of meeting the city's projected demands. The intake was insufficient to meet the 3 MGD projection. Alternative intakes were evaluated, including a new intake closer to the dam and expansion of the existing intake.
Burns & McDonnell evaluated methods to expand plant production to 3 MGD and enhance the performance of existing processes. Reduction of taste and odor was paramount. This was complicated by the presence of manganese in the water and a lake supply that was difficult to treat with the plant's existing processes. Four process alternatives were developed based on bench scale testing with new coagulants, PAC, ozone and ultraviolet (UV)/peroxide treatment. These alternatives were developed through the preliminary concept design phase. Life cycle costs were projected to compare the options.
The project included a process, regulatory compliance and hydraulic evaluation of the plant, and a process, architectural, electrical, mechanical and structural condition assessment. The process evaluation included a performance-based assessment for each treatment process to improve treatment performance and reduce operating costs. Ozone testing included a continuous-flow bench-scale unit that combined the reliability of pilot-scale testing with the cost-effectiveness of bench-scale methods. Ozone dose, demand, decay, CT credit and bromate formation curves were developed to determine the ozone dose required to achieve disinfection, color reduction, taste and odor abatement, and oxidation goals.
- Taste and odor reduction
- Treatment process optimization
- Disinfection byproduct reduction
- Bench and field testing
- Ozone evaluation
- UV peroxide evaluation
- PAC evaluation
- Regulatory review
- Water treatment plant hydraulic evaluation
- Lake sediment/BMP evaluation
- Yield analysis
- Water treatment plant condition assessment
- Code review
- Backup supply evaluations
- Alternative development
- Life cycle costing